Analisis temporal de los resultados de la calibración de ecosondas científicas en buques de investigación.

El Instituto Español de Oceanografía (IEO), en sus campañas de Evaluación Acústica de Recursos Pesqueros, utiliza ecosondas científicas para estimar la biomasa de las especies pelágicas de interés comercial, como la sardina y la anchoa. Para la utilización cuantitativa de los resultados de estas ecosondas, es fundamental la exactitud de las medidas, así como su estabilidad temporal. Por esta razón, las ecosondas son calibradas antes del comienzo de cada campaña. Este trabajo presenta un análisis temporal de las calibraciones de las ecosondas científicas de los distintos Buques de Investigación, que el IEO ha utilizado a lo largo de los años.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

A Machine Learning Based Full Duplex System Supporting Multiple Sign Languages for the Deaf and Mute

This manuscript presents a full duplex communication system for the Deaf and Mute (D-M) based on Machine Learning (ML). These individuals, who generally communicate through sign language, are an integral part of our society, and their contribution is vital. They face communication difficulties mainly because others, who generally do not know sign language, are unable to communicate with them. The work presents a solution to this problem through a system enabling the non-deaf and mute (ND-M) to communicate with the D-M individuals without the need to learn sign language. The system is low-cost, reliable, easy to use, and based on a commercial-off-the-shelf (COTS) Leap Motion Device (LMD). The hand gesture data of D-M individuals is acquired using an LMD device and processed using a Convolutional Neural Network (CNN) algorithm. A supervised ML algorithm completes the processing and converts the hand gesture data into speech. A new dataset for the ML-based algorithm is created and presented in this manuscript. This dataset includes three sign language datasets, i.e., American Sign Language (ASL), Pakistani Sign Language (PSL), and Spanish Sign Language (SSL). The proposed system automatically detects the sign language and converts it into an audio message for the ND-M. Similarities between the three sign languages are also explored, and further research can be carried out in order to help create more datasets, which can be a combination of multiple sign languages. The ND-M can communicate by recording their speech, which is then converted into text and hand gesture images. The system can be upgraded in the future to support more sign language datasets. The system also provides a training mode that can help D-M individuals improve their hand gestures and also understand how accurately the system is detecting these gestures. The proposed system has been validated through a series of experiments resulting in hand gesture detection accuracy exceeding 95%Funding for open access charge: Universidad de Málag

Training Scientific Communication Skills on Medical Imaging within the Virtual World Second Life: Perception of Biomedical Engineering Students

Second Life is a multi-user virtual world platform which enables online learning through immersive activities. This study evaluates the perception of third-year biomedical engineering students about learning activities complementary to a biomedical imaging course carried out within Second Life and focused on training in the public presentation of scientific content to their peers. Between 2015 and 2017, students gave oral presentations on medical imaging topics selected from the proposals of their classmates. Participants were invited to complete an evaluation questionnaire. In the three years of the study, 133 students enrolled in the course (48, 46, and 39 consecutively), and 97 of them delivered the questionnaire (48%, 83%, and 92%, consecutively). Attendance at the sessions ranged between 88% and 44%. The students positively value the experiences, especially the teacher, the educational content, and the virtual island environment, with mean scores greater than or equal to 8.4, 7.7, and 7.7, respectively, on a 1–10-point scale. Overall, they valued Second Life as an attractive and suitable environment for their training in science communication skills, in which they gain self-confidence and are less afraid of speaking in public. Second Life enables students to present scientific content effectively to their peers, receiving hands-on training in the tasks of collecting, organizing, and presenting data, with the benefits of remote access, collaborative work, and social interaction.This research was founded by the Educational Innovation projects of the University of Malaga PIE13-072, PIE15-150, PIE17-113 and PIE19-217. Funding for open access charge: Universidad de Málaga/CBUA and Andalusian Plan for Research, Development, and Innovation (PAIDI): TIC128. Partial funding for open access charge: Universidad de Málag

First steps towards developing an open access software designed for the recognition of daily microstructures used in ageing fish

Ageing methods for most of the exploited fish species are not validated, and consequently age data series often have important gaps and uncertainty manifesting its consequences on age-based fisheries assessment. Amongst the most recognizable otolith microstructures are those corresponding to daily growth increments producing reliable estimates of larval and juvenile growth in an ample number of fish species. From the temporal perspective, otoliths are the only calcified structures that show growth marks at two different scales, the seasonal and daily markings. Seasonal rings or otolith macrostructure is mostly used to age juvenile and adult individuals while microstructure is typically used in larvae, because the DGI in adult otoliths are too numerous and cumbersome to count. Nonetheless, in several hake species DGI have been counted and measured in juveniles by interpretating daily increments through thin transversal sections of the otolith (50-100 μ). Since these sections can only be obtained after a process of otolith resin embedding, section precision cutting and final polishing, the main handicap lacking today is the appropriate digital tool for counting and measuring otolith DGI widths. In this communication, the research multidisciplinary team of researchers from the research fields of fisheries and engineering plans to develop a new tool designed to add efficiency in the weighty task of estimating the age of fishes based on DGI analysis. The technique is based on new computer algorithms that interpret DGI patterns, whether it be in a semi-automatic way or in such a manner that otolith readers are allowed to interact with the system or run automatically when the technique finds determined types of otolith structural patterns considered consistent and reliable. The technique, when registered, will be made available freely to the international scientific community in the open access mode. Although some image analysis software is available in the market nowadays, including some centered in otolith image processing, they all show at least two main restrictions: they do not manage ‘live’ images which allow to specifically focus determined microstructures at great magnification, and moreover, the high costs of the software. We present here the first results on the development of this forthcoming software which is expected to resolve the before mentioned limitations. Larval and adult otoliths measure from some hundred μm to several mm, respectively, while DGI widths fluctuates from slightly less than 1 μm increments close to the nucleus in larval otoliths to more than 15 μm in juveniles and adults. In order to discriminate DGI, light microscope magnification varies from x1000 in larvae to x200 in juveniles and adults. As a consequence, most of the times the whole otolith or section cannot be represented on a single image and thus, several images are needed to construct a sole image to get the vision of the total otolith size that can be measured where most DGI counts can be included. In these cases, the image series should be tiled as a panoramic view or mosaic, where each section superposes with adjacent ones. The first step in the software development has been a superposing routine, identifying automatically common areas between adjacent images. Once a single high quality image is set by otolith at an acceptable magnification some arrangements on contrast, brightness, etc. can be implemented when desired. The next stage is the controlled or semi-automatic counting of DGI along a growth trajectory. Expert readers particular interpretations could be matched to those made au- tomatically and eventually adjust the software reading standards. Finally, DGI counts and measurement data are recorded and also exported to work files, where further analysis could be performed.As soon as having ready an appropriate and affordable tool to count and measure daily growth incre- ments in an automatic or semi-automatic way, otolith microstructure analysis can have a reliable age estimation method that can be extended and applicable to age adult fish. Although, in its present form the technique is focused in otolith microstructure analysis, further developments of the initiated software development intends to extend its application to other calcified structures, namely bivalve shells and cephalopod peaks.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

A small open economy New Keynesian model for a foreign exchange constrained economy

Firms in many low income countries depend entirely on imported capital and intermediate inputs. As a result, in these countries economic activity is considerably influenced by the capacity of the economy to import these inputs which, in turn, depends on the availability and cost of foreign exchange. In this study we introduce foreign exchange availability as an additional constraint faced by firms into an otherwise standard small open economy New Keynesian DSGE model. The model is then calibrated for a typical Sub Saharan African economy and the behaviour of the model in response to both domestic and external shocks is compared with the standard model. The impulse responses of the two models show that the modified model generates more variability in most of the variables considered than the standard model. This behaviour of the modified model seems to correspond to the stylized facts of low income countries

Long-term calibration analysis of scientific echosounders used in research vessels

The use of scientific multifrequency echosounders like SIMRAD EK60 in resource-assessment surveys of small pelagic fish like sardine or anchovy, has been employed by the Spanish Institute of Oceanography (IEO) for more than thirty years. The quantitative use of its data for biomass estimations, makes necessary that accurate echosounder calibrations are done at the beginning of the acoustics surveys. Echosounder stability over time, is fundamental to guarantee the consistency of the annual results and to ensure their comparability. This paper shows a long-term comparison study of the calibrations of SIMRAD EK60 echosounders that were installed in different Research Vessels (R/V), carried out in different locations and in different seasons. A study of calibration results was carried out by three different methods; the first of them, using a specific echosounder software tool, the second using an ad-hoc design optimization algorithm over previous software selecting and filtering data and finally, using an algorithm recommend by ICES, doing an optimization of raw data.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

New open access software designed for the recognition of daily microstructures used in ageing fish

Ageing methods for most of the exploited fish species are not validated, and consequently age data series often have important gaps and uncertainty manifesting its consequences on age-based fisheries assessment. In this communication, the research multidisciplinary team of researchers from the research fields of fisheries and engineering plans to develop a new tool designed to add efficiency in the weighty task of estimating the age of fishes based on DGI analysis. The technique is based on new computer algorithms that interpret DGI patterns, whether it be in a semi-automatic way or in such a manner that otolith readers are allowed to interact with the system or run automatically when the technique finds determined types of otolith structural patterns considered consistent and reliable. The technique, when registered, will be made available freely to the international scientific community in the open access mode. Although some image analysis software is available in the market nowadays, including some centered in otolith image processing, they all show at least two main restrictions: they do not manage ‘live’ images which allow to specifically focus determined microstructures at great magnification, and moreover, the high costs of the software. We present here the first results on the development of this forthcoming software which is expected to resolve the before mentioned limitations. As soon as having ready an appropriate and affordable tool to count and measure daily growth increments in an automatic or semi-automatic way, otolith microstructure analysis can have a reliable age estimation method that can be extended and applicable to age adult fish. Although, in its present form the technique is focused in otolith microstructure analysis, further developments of the initiated software development intends to extend its application to other calcified structures, namely bivalve shells and cephalopod beaks.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Calibración de los parámetros del modelo de directividad de los transductores de la ecosonda Simrad EK60

The scientific echo sounder Simrad EK60 could be used for quantification of fisheries resources in marine science research campaigns. They use different frequency channels (from 18 to 200 KHz), emitted by underwater sound transducers with circular aperture geometries. Calibration is essential to obtain reliable values of Ts (Target Strength) and Sv (Volume Backscattering Coefficient) parameters, which are used to estimate fisheries stocks using echo volume integration. In this paper, manufacturer’s calibration method is presented, together a new proposal for the acquisition and post-processing of calibration data to obtain more accurate results.La ecosonda científica Simrad EK60 se utiliza para cuantificar los recursos pesqueros en campañas de investigación oceanográfica, utilizando diferentes canales de frecuencias (de 18 a 200KHz) mediante transductores acústicos de apertura con geometría circular. Su calibración resulta esencial para obtener los valores de Ts (‘target strength’) y Sv (‘Volume backscattering coefficient’), necesarios para estimar los tamaños de los stocks de las pesquerías mediante integración de los ecos. En este trabajo se presenta el método de calibración propuesto por el fabricante, así como una nueva propuesta de obtención y postproceso de datos que permite obtener calibraciones fiable

Quantifying Ant Activity Using Vibration Measurements

<div><p>Ant behaviour is of great interest due to their sociality. Ant behaviour is typically observed visually, however there are many circumstances where visual observation is not possible. It may be possible to assess ant behaviour using vibration signals produced by their physical movement. We demonstrate through a series of bioassays with different stimuli that the level of activity of meat ants (<i>Iridomyrmex purpureus</i>) can be quantified using vibrations, corresponding to observations with video. We found that ants exposed to physical shaking produced the highest average vibration amplitudes followed by ants with stones to drag, then ants with neighbours, illuminated ants and ants in darkness. In addition, we devised a novel method based on wavelet decomposition to separate the vibration signal owing to the initial ant behaviour from the substrate response, which will allow signals recorded from different substrates to be compared directly. Our results indicate the potential to use vibration signals to classify some ant behaviours in situations where visual observation could be difficult.</p></div

Training Scientific Communication Skills on Medical Imaging within the Virtual World Second Life: Perception of Biomedical Engineering Students

Second Life is a multi-user virtual world platform which enables online learning through immersive activities. This study evaluates the perception of third-year biomedical engineering students about learning activities complementary to a biomedical imaging course carried out within Second Life and focused on training in the public presentation of scientific content to their peers. Between 2015 and 2017, students gave oral presentations on medical imaging topics selected from the proposals of their classmates. Participants were invited to complete an evaluation questionnaire. In the three years of the study, 133 students enrolled in the course (48, 46, and 39 consecutively), and 97 of them delivered the questionnaire (48%, 83%, and 92%, consecutively). Attendance at the sessions ranged between 88% and 44%. The students positively value the experiences, especially the teacher, the educational content, and the virtual island environment, with mean scores greater than or equal to 8.4, 7.7, and 7.7, respectively, on a 1&ndash;10-point scale. Overall, they valued Second Life as an attractive and suitable environment for their training in science communication skills, in which they gain self-confidence and are less afraid of speaking in public. Second Life enables students to present scientific content effectively to their peers, receiving hands-on training in the tasks of collecting, organizing, and presenting data, with the benefits of remote access, collaborative work, and social interaction